Field
Exemplary embodiments relate to device fabrication, and, more particularly, to a method and apparatus for plasma etching.
Discussion
Within the realm of semiconductor device fabrication, plasma etching may be used to form a pattern on or in a substrate. That is, plasma etching may be utilized to pattern the bulk of a substrate or to pattern one or more layers formed on the substrate, such as one or more conductive and/or dielectric layers. As such, a semiconductor fabrication process may include the formation of a material layer on a substrate via a deposition process, an exposure process to form a mask pattern in the material layer, and a plasma etching process to selectively etch underlying material utilizing the mask pattern. Plasma etching may provide relatively finer resolution than other conventional etching techniques.
Plasma etching typically involves the formation of a plasmarized (i.e., ionized) reactive gas in a chamber containing a specimen to be etched. The ionized reaction gas diffuses toward the specimen to enable chemisorption to occur between reactive particles of the plasma and a material surface of the specimen exposed via a masking layer. Reactions produce desorbed molecules that diffuse back into a mainstream etchant flow to be removed from the chamber. In this manner, the exposed material surface may be etched according to a pattern of the masking layer; however, the resolution of the resulting pattern may be affected by the etching selectivity between the exposed material and a material of the masking layer. As such, improvements in etching selectivity may enable increases in pattern resolution.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept, and, therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.